- add FShaderSource class which wraps source as populated by preprocessing and subsequently accessed by compilation and other debug features; this class automatically inserts zeroed padding such that 16-byte-wide SIMD string comparison operations do not require a non-SIMD tail to process any overhang.
- add typedefs for the string/view/character types and update preprocessing code to use these typedefs instead of the explicit types
- add explicit if constexprs in minifier code around char width to disable simd optimizations for char width != 2 (and subsequently skip the non-simd tail if char width == 2 since FShaderSource automatically adds the required padding)
#rb Jason.Nadro, Yuriy.ODonnell
[CL 30358137 by dan elksnitis in ue5-main branch]
- move sequence of preprocessing steps out of ShaderPreprocessor module and into UE::ShaderCompilerCommon::ExecuteShaderPreprocessingSteps; the former is now explicitly just the low-level preprocessor lib
- add an implementation of PreprocessShader in FBaseShaderFormat so backends which have no custom code to execute as part of preprocessing can just automatically inherit this implementation, and fix up such backends to eliminate now-unnecessary overrides
#rb christopher.waters, Laura.Hermanns
[CL 30178136 by dan elksnitis in ue5-main branch]
- move uniform buffer cleanup and dead stripping into ShaderPreprocessor module's PreprocessShader function
- add "required symbols" to compiler input struct to specify additional symbols to keep during minification aside from those specified by the entrypoint; modify API such that both an entry point string and additional symbols can be specified (to avoid each backend needing to manually parse the compound RT entry point string)
- make use of ModifyShaderCompilerInput in all backends to set additional defines and required symbols on input struct up front; only use the AdditionalDefines map in cases where it's actually necessary
- remove the various per-platform defines for enabling minifier, no longer required now that this has been rolled out for all backends
- fix SCW directcompile mode; this had rotted due to pieces of the FShaderCompilerEnvironment having been added that weren't explicitly serialized to either cmdline or in the shader source. this now serializes as a base64 string written inside the USF containing all portions of the environment required for compilation (using the same serialization function as is used to write/read the SCW input file)
- use a debug flag for indicating we're in "direct compile" mode and should load the debug USF off disk, rather than the poorly named "bSkipPreprocessedCache" (this name is both inaccurate and also confusing due to the addition of the preprocessed job cache)
- modify platform "force wave32" mechanism to use a pragma directive to set a compiler define, instead of doing string replacement in the preprocessed source
- add a view version of the RT entrypoint parsing to use in preprocessing, note that other paths still need to construct fstrings due to further manipulation so keeping the FString path around too
- clean up backends manually checking the "directcompile" cmdline arg
#rb christopher.waters, Yuriy.ODonnell
#rb Chris.Waters
#rb Laura.Hermanns
[CL 30023082 by dan elksnitis in ue5-main branch]
- Removing the need for COMPILER_DEFINE on GetResourceFromHeap and GetSamplerFromHeap
- FShaderParameterParser constructor now requires a FPlatformConfiguration object that each shader format can configure.
- FPlatformConfiguration::GenerateBindlessAccess allows each platform to generate the code for accessing a bindless resource or sampler.
- Added EShaderParameterParserConfigurationFlags to specify support for stable constant buffers and bindless.
- Moved EBindlessParameterMode into EShaderParameterParserConfigurationFlags::BindlessUsesArrays
- While moving things around, I was able to convert some TCHAR* uses to FStringView
#jira UE-166341
#rb mihnea.balta
[CL 29533376 by christopher waters in ue5-main branch]
- Changing all shader versions to Guid.
- Fixing shader version guids in shaders to not be in comments.
- Adding a shader version to RayTracingCommon.ush.
#rb dan.elksnitis, Jason.Nadro, Yuriy.ODonnell, Laura.Hermanns
[CL 29168287 by christopher waters in ue5-main branch]
- Splitting "Bindless Resource" shader parameter types into "Bindless SRV" and "Bindless UAV" to make sure reflection/binding validation is correct.
#jira UE-166341
#rb jeannoe.morissette
[CL 28995862 by christopher waters in ue5-main branch]
- When generating Uniform Buffer HLSL code, a 'static const struct {} Name' was created which has been causing compiler issues off and on for years.
- When RemoveUniformBuffersFromSource removed said struct, it parsed the struct's structure to figure out how to translate UniformBuffer.Member into UniformBuffer_Member in code that accessed Uniform Buffers.
- Now, instead of a struct, a "UniformBuffer <Name>" declaration is created and filled with mappings from "UniformBuffer.Member" into the correct code.
- This allows ConstantBuffer objects to be used differently from cbuffer where the former generates "UniformBuffer.Member" and the latter generates "UniformBuffer_Member"
- This also allows resources to always be translated to "UniformBuffer_Member"
- Shader define 'PLATFORM_SUPPORTS_UB_STRUCT' is now 'PLATFORM_SUPPORTS_CONSTANTBUFFER_OBJECT' and will be set on shader formats that support ConstantBuffer<> objects.
- Removed lots of unused code from BindlessResources.ush
#jira UE-195103
#rb dan.elksnitis, jeannoe.morissette
[CL 28058373 by christopher waters in ue5-main branch]
